Webinar 2. Finding and Quantifying Credits

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2 Webinar 1. Overview Webinar 2. Finding and Quantifying Credits Webinar 3. Developing a Plan Webinar 4. Implementing and Verifying Offsets

3 Adaptive Management Technical Handbook Released: 01/07/ (topic keyword: adaptive management ) Implementing Water Quality Trading in WPDES Permits Released: 08/21/2013 Water Quality Trading How-To Manual Released: 09/09/ (topic keyword: water quality trading )

4 Finding Offsets Quantifying Offsets with SNAP+ Converting Offset to Credits Questions

5 Step 1 Decide if Adaptive Management/Trading is right for the point source & their partners Step 2 Step 3 Work with partners to develop the Adaptive Management/Trading plan Submit Plan to WDNR Permit will be reissued/modified to include Adaptive Management/Trading requirements (requirements differ between AM and trading) Step 4 Comply with permit requirements and implement Adaptive Management/ Trading plan (requirements and timing differ between AM and trading)

6 Voluntary compliance options for WPDES permit holders to comply with phosphorus requirements Options will be used when it is economically preferable to control nonpoint sources or other point sources of P Both require nonpoint and/or other point source reductions

7 Determine your eligibility for the programs. Evaluate information contained in TMDLs and use DNR screening tools to evaluate potential opportunities. Work with the county LCDs, crop consultants, and watershed groups to refine information and help make contact with potential land users. Perform field scale analysis to quantify reductions and convert reductions to credits (WQT).

8 PRESTO: Calculates basin specific average annual phosphorus loads from point and nonpoint sources Performs three tasks: Watershed Delineation, Effluent Aggregation, and Pollutant Runoff Watershed Delinea.on Effluent Aggrega.on Pollutant Runoff

9 What s available? Look up tool GIS Model User Manuel search PRESTO

10 Visit DNR website for information on TMDLs in the watersheds of interest: Review TMDL reports to evaluate potential needed load reductions. TMDLs may have ranked watersheds by loadings or characterized different reductions scenarios. For WQT, TMDLs set the credit threshold and for AM provide an estimate of reductions needed to reach water quality criteria.

11 A screening / potential index model developed by: Aaron Ruesch and Theresa Nelson, P.E. Wisconsin Department of Natural Resources The Model DOES NOT estimate a mass load (pounds/acre) of pollutants. The model does reduce the need to inventory all fields in watershed every year and helps focus efforts on high risk areas.

12 0.45 Correlation between Erosion and Phosphorus Total Phosphorus Concentration (mg / L) Total Suspended Sediment Concentration (mg / L)

13 LiDAR-Based GIS Tool Uses readily available data Helps prioritize fields most vulnerable to erosion and phosphorus export Combines 3 components: USLE (sheet erosion) Stream Power Index (gullies) Non-contributing areas USLE SPI NC

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17 Overall erosion score Erosion Score High Medium Low

18 Where are the animals? Animal lots

19 Which fields are near surface water pathways? Minimum Distance On stream Far Away

20 Where are farmers already working to curb erosion? Grassed Waterway Contour cropping

21 Where can we restore wetlands? Potentially restorable wetlands

22 Putting the Pieces Together LEGEND Distance from animal lot to stream ft > 300 Crop Rotation High Erosion Score Non-contributing areas Pot. Restorable Wetlands Continuous Corn Cash Grain Dairy Pasture/Hay/Grassland Not enough data

23 Decision framework for identifying Critical Source Areas (CSAs) of non-point source nutrient pollution and prioritizing best management practices (BMPs) on agricultural fields.

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25 Credits Generated by a Nonpoint Source Modeling vs. Monitoring SNAP-Plus and RUSLE2 for agricultural field practices New Barnyard Tools SLAMM and P-8 for urban practices Credits Generated by a Point Source Effluent monitoring

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27 Wisconsin P Index P Index estimates P delivery to nearest surface water body Accounts for sources and transport based on long-term average weather Field Runoff Annual field-edge runoff losses estimated for each crop year: Sediment-bound P Dissolved P from soil Dissolved P from manure and fertilizer x Total P field to stream delivery ratio: Applied to account for P deposition and infiltration Assumes channelized flow similar to a grassed waterway Stream = Annual P delivery to stream (P Index)

28 County Soil Type Soil Test P and Organic Ma<er Field Slope Field Slope Length Tillage RotaAon crops and yields Manure ApplicaAons P FerAlizer ApplicaAons Downfield Slope to Surface Water Distance to Surface Water Stream P Delivery Factors Field Assumes grassed waterway or channelized flow Does not account for gully erosion

29 Soil P Manure P on surface Fertilizer P on surface Eroding sediment - RUSLE2 erosion P and Soil Transport Rainfall runoff - Runoff curve numbers Snowmelt runoff - Method based on surface depressional storage and long-term average runoff for agricultural watersheds

30 Average annual rill and interrill erosion on a slope in T/acre/year Erosion = R x K x L x S x C x P RUSLE2: Basic equation for average annual soil loss (a) on each ith day is: a i = r i k i l i S c i p i r i = erosivity factor k i = soil erodibility factor l i = slope length S = slope steepness c i = cover management factor p i = supporting practices factors P Index s Particulate P loss is tightly correlated with soil loss as modeled by USDA s RUSLE2.

31 Testing Source Components of P Index Equations Revised WI P Index compared to measured runoff losses for 86 site years using measured sediment and runoff volume in the equations WPI with meas. sediment and runoff kg ha y = 0.97x r 2 = :1 Field Stream Measured total P kg ha -1 P Index is working relatively well to rank fields by total P loss if the methods used to estimate average annual runoff and sediment loss are accurate. Source: Good, L.W., P. Vadas, J.C. Panuska, C.A. Bonilla, W.E. Jokela, Testing the Wisconsin Phosphorus Index with Year-Round Field-Scale Runoff Monitoring. Journal of Environmental Quality. 41:

32 20 1:1 WI P Index Measured runoff total (P lb acre - 1 yr - 1 ) The P Index estimates P loss under long-term average weather and real weather is variable from year-to-year. Over the long-term the correlation is better as the variability balances out.

33 Tillage: Fall chisel, twisted shovel, spring disking, field cultivation Erosion (T/a/yr) Part. P Index Total Runoff (in) Soluble P Index Total P Index Corn silage Corn grain Soybean Winter wheat

34 Transport Factors and P Index for Continuous No-till Crops Tillage: No-till Erosion (T/a/yr) Part. P Index Runoff (in) Sol. P Index Total P Index Corn silage Corn grain Soybean Winter wheat

35 Soil Loss (T/a/yr) Part. P Index Sol. P Index 15,000 gallons/acre slurry, fall, surface applied, no-till ,000 gallons/acre slurry, fall, incorporated with chisel plow Higher dissolved P losses with no-till Higher particulate P losses with incorporation by tillage

36 P Index Varies with Management: NE Wisconsin Example Rotation: 3 years corn silage and 3 years alfalfa Soil test P = 70 ppm Manawa silty clay loam soil, 2% slope Fall chisel, fall apply 10,000 gal/acre dairy manure 1.3 T/a/yr erosion No till, fall apply 10,000 gal/acre dairy manure 0.5 T/a/yr erosion No till, winter apply 7,000 gal/acre dairy manure 0.5 T/a/yr erosion Tillage Influence Manure Timing and Method Influence

37 Constants Soil type (CaC 8% slope) Soil test values (P= 65ppm) Field Characteristics Size (40acres) Distance and slope to water 2-6%) Crop Management 7 yr rotation Yield goals Manure applications Corn: 10,000 gal/acre, slurry, fall applied, unincorporated Soybeans: 10 T/acre, semi-solid, fall applied, incorporated (300ft,

38 Changing Factors Tillage (on/off contour, tillage type) With or without cover crops Rotations Buffers Snap Features ~230 crop types 11 tillage types Annual and rotational average PI values Soluble and Particulate PI values

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45 Field 1 (Dairy Rotation, no BMPs) 1-A1 (Dairy + Buffer) 2 (Corn-Soy, No BMPs) 2-A1 (Corn-Soy, no till) 2-A2 (Corn-Soy w/cover) 2-A3 (Whole Field) PI Yr 1 PI Yr 2 PI Yr 3 PI Yr 4 PI Yr 5 PI Yr 6 PI Yr 7 Rot. Ave Soil Loss / /0.2

46 Wisconsin P Index Planning tool biases: Assumes single slope for entire field Uses dominant critical slope Assumes gullies are protected by grassed waterway Does not account for P losses to tiles Does not model channel processes (SPARROW does this) Field Stream

47 P Index Website: SnapPlus Website: Contact Information: Sara Walling, DATCP, Laura Ward Good, UW Madison Soil Science Dept,

48 Annual Phosphorus Loss Estimator (APLE) for Barnyards Under development by Peter Vadas, USDA-ARS Estimates sediment and P in runoff per acre per year using: Surface type (dirt or paved) Soil test P Number of animals manure generated, Average annual rainfall (uses to estimate runoff)

49 What is a credit? A credit is a unit of pollutant reduction usually measured in pounds equivalent. Credits can be generated by a point source over-controlling its discharge or by a nonpoint source installing best management practices (BMPs) beyond the credit threshold. DNR negotiated concept of interim credits.

50 Size of watershed and location of point sources relative to potential credits. Relative location of point of standards application. Assess need for downstream trading or delivery factors due to lakes or impoundments how will this impact trade ratios or attainment of water quality standards.

51 Trade ratios are used to ensure the amount of reduction resulting from the trade has the same effect as the reduction that would be required without the trade. Further requires an improvement in water quality. Trade ratio components include: 1. Location 2. Delivery 3. Uncertainty 4. Equivalency 5. Retirement

52 2.7 Pollutant Reduction Credit Threshold Credit threshold is the pollutant load below which reductions must be made to generate pollutant reduction credits. PS CG Most restrictive effluent limit (permitted MS4, 20% TSS reduction) NPS CG Current pollutant load or LA when TMDL approved 2.8 Interim and Long-term Pollutant Reduction Credits for NPSs Located in a TMDL Watershed TMDL Credit Threshold Apply % Reduction from TMDL to the baseline condition in TMDL. Baseline NR 151 (PI= 6) Barnyards and Stream bank Stabilization

53 2.9 Technical Standards for Management Practices NRCS or WDNR 2.10 Location and Geographic Extent of Water Quality Trades TMDL WQBELs Credits generated within drainage area of impaired segment Non-TMDL WQBELs Credits generated upstream of point of standards application (POSA)

54 2.11 Trade Ratios (Delivery + Downstream + Equivalency + Uncertainty - Habitat Adjustment):1 Minimum Trade Ratios equal 1.1:1 for PS CG, 1.2:1 for NPS CG 2.12 Timing of Pollutant Reduction Credit Generation PS CG - Must comply with trade agreement permit limit NPS CG - BMP in place and effective 2.13 Timing of Pollutant Reduction Credit Use PS CG - Credits must be generated during compliance period NPS CG - Anytime during calendar year 2.14 Quantifying Pollutant Load Reductions PS CG - Effluent monitoring NPS CG - Method specified by guidance

55 Final Trade Ratio = Delivery + Equivalency + Uncertainty Habitat Adjustment For trades involving nonpoint sources the trade ratio cannot be lower than 1.2:1 (1.2 pounds of nonpoint for every pound of point source pollutant). For trades located upstream in the same HUC-12 the equation generally simplifies to: Final Trade Ratio = Uncertainty : 1 ( add 0.2 if necessary)

56 Equivalency (form of pollutant) Not necessary with phosphorus Not yet specified for N and TSS (sediment) Delivery (distance between generator and user) TMDL Same factors used in TMDL or USGS SPARROW Non-TMDL USGS SPARROW model for P, N and sediment Not needed if trading within same HUC-12

57 Delivery Factor = (1/SPARROW delivery fraction) - 1

58 Downstream Trade Ratio Factor: Allow downstream trading in same HUC-12 but minimize risk of exceedances of water quality criteria. Percent Difference between Buyer s Load and Total Load at Point of Discharge Downstream Trade Ratio Factor < 25% % % % > 0.8

59 Point Source Credit Generator Uncertainty Factor: The uncertainty factor for the trade is set equal to 1 when the credit generator performs effluent monitoring in accordance with the terms of its WPDES discharge permit. Due to the nature of stormwater discharges, nonpoint source uncertainty factors are more appropriate for a permitted MS4.

60 Nonpoint Source Credit Generator Uncertainty Factor: For the purpose of this uncertainty factor, MS4s and other permitted storm water sources are considered nonpoint because the pollutant source is diffuse and dependent on climatic factors. Generally, the nonpoint source uncertainty factor accounts for the effectiveness of management practices employed over various flow or precipitation regimes and the ease of verification that the management practice is in place and operating effectively.

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63 40 acre field Dairy Rotation with a buffer added (2:1 Uncertainty Trade Ratio) Credit Threshold: Annual PI = 3 (TMDL call for a 50% reduction from NR 151 standards) Not located downstream and no delivery factor needed

64 Summary of PI for installation of buffer strip on a dairy rotation Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Rota.on Average Field 1 Dairy Rota.on (lb/ac/yr) Field 1- A1 Dairy + Buffer (lb/ac/yr) Load Reduc.on (lb/ac/ yr) Field located in a TMDL watershed with Credit Threshold of 3 Interim Load Reduc.on (lb/ac/yr) Long- term Load Reduc.on (lb/ac/yr)

65 Interim Load Reduc.on (lb/ac/yr) Long- term Load Reduc.on (lb/ac/yr) Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Installation of buffer strip Trade Ratio 2:1 Rota.on Average Interim Credits (lb/ac/yr) Long- term Credits (lb/ac/yr) acre field Total Interim Credits (lb/yr) Total Long- term Credit (lb/yr)

66 40 acre field Corn Soybean Rotation with whole field management (1:1 uncertainty Trade ratio) Credit Threshold Not Applicable Located downstream but no delivery factor needed. Presto analysis shows point source averages 42% of total load.

67 Summary of PI for whole field management Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Rota.on Average Field 1 Corn Soybean (lb/ac/yr) Field 1- A1 Whole Field (lb/ac/yr) Load Reduc.on (lb/ac/ yr) Field not located in a TMDL, no credit threshold Interim Load Reduc.on (lb/ac/yr) Long- term Load Reduc.on (lb/ac/yr)

68 Interim Load Reduc.on (lb/ac/yr) Long- term Load Reduc.on (lb/ac/yr) Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Rota.on Average Trade Ratio: whole field manament (1:1) plus downstream (0.2) results in trade ratio of 1:1.2 Long- term Credits (lb/ac/yr) acre field Total Long- term Credit (lb/yr)

69 Determine your eligibility for the programs. Evaluate information contained in TMDLs. Use DNR screening tools to evaluate potential opportunities (work with county LCDs, crop consultants, and watershed groups). Perform field scale analysis to quantify reductions (work with county LCD and crop consultants). Apply applicable trade ratios.

70 Guidance for Implementing Water Quality Trading in WPDES Permits A Water Quality Trading How To Manual (topic keyword: water quality trading ) Adaptive Management Technical Handbook (topic keyword: adaptive management )